Infantile spasms are a severe type of seizures which occur in infants. The outlook for a child with infantile spasms is poor: most are developmentally disabled, and a majority continue to have severe epilepsy. ACTH is the most commonly used treatment for infantile spasms and is successful at least temporarily in about 70% However, adverse effects are significant. Conventional anticonvulsants are only occassionally effective. Vigabatrin, a new anticonvulsant, is being evaluated for safety and efficacy in treating infantile spasms.